The speed would depend on where you are located
but overall it should be slightly faster than the 3g if i remember correctly.
If you need a device that shoots out internet service
you can get a smart phone since most of the devices can shoot out the mobile internet as a hotspot wifi line.
If you have the right visa and have ailen card just get a smart phone and use the hot spot to connect it to your laptop or any sort.

i already have a smartphone that can act as a hotspot, but i'd rather have a dedicated device, especially if it's faster. from what i gathered on the KT website, they offer unlimited 4G which would be pretty sweet.

There have been some topics about this if you do a search. I would describe the egg as decent. The speeds are good - I've never actually tested it but it is certainly faster than 3G. I pay about 12,000 per month for 30gb. That is on a two year contract, and I've heard you can get a shorter contract for not much more if you try. The coverage isn't quite as good as a 3G network, but it isn't bad. The weak point is definitely the battery - at least on the slim egg that I have (I think there is a version with a higher capacity battery). Not only does the battery run out quickly, but it drains itself even when not being used after just a couple of days. To make things worse, it uses a proprietary cable so you can't simply USB charge it if it runs out while you're on the road, you have to USB charge it using the special USB cable made for this device. A minor problem, but still annoying. Overall, I've been happy with it but I often find myself just using the 3G on my iphone even when I am over my allotted data and I have the egg in my bag. If you plan on sitting in a cafe for a few hours on your computer, or you have many different devices with wifi, the egg is probably a good idea. If you want to have a persistent connection readily available when you are out and about, however, the egg will fail you. If I could do it again, I'd probably opt to wait for an LTE phone and simply tether. That being said, I only pay 12,000 a month.

Speed is much better than 3G. I actually have two of them: an older model and newer model. Newer model is nice because battery lasts about 8 hours, while the older model lasts about 2-3 hours. Bad thing about the newer model is that it allows for only 3 devices at once, the older model allows 5 devices. They might have a latest modl that gets 8+ hours and allows for more than 3 devices to be connected at once. Anyways its a lot cheaper than LTE and offers speeds that approaches that.